While interfaces are typically viewed as a dividing layer between two neighboring materials, the properties of the interface are at times radically different from the constituent materials. In nanomaterials, nearly 20% to 30% of the total atoms are located at or very close to the surface. Nanomaterials thus provide an ideal platform to study these effects. Rational engineering of the interfaces between two different components of a nanomaterial presents an opportunity for creating materials with novel properties that cannot be achieved otherwise.